1. Field of the Invention
This invention relates to an indirect extrusion press which includes a cleaning ring and a loose die, and more particularly to a clamp mechanism of the indirect extrusion press of the type mentioned which clamps the cleaning ring upon handling.
2. Description of the Related Art
An indirect extrusion press for use for indirect extrusion of aluminum alloy material is already known and disclosed, for example, in Japanese Utility Model Publication Application No. 61-42649.
The indirect extrusion press is shown in FIG. 8. Referring to FIG. 8, the indirect extrusion press includes a cleaning ring 3 removably fitted at an end portion of a die stem 1 and adapted to clean the inner face of a container 2. A loose die 4 is removably mounted at the end of the die stem 1, and a handling apparatus 5 is provided for clamping and handling the cleaning ring 3 and the loose die 4.
After indirect extrusion of material, the cleaning ring 3 and the loose die 4 at the end of the die stem 1 are protruded outwardly from an adjacent end of the container 2, clamped by clamp members of the handling apparatus 5 and removed in an axial direction from the die stem 1 by the handling apparatus 5.
The prior art indirect extrusion press, however, has a drawback that, since the cleaning ring 3 has a small axial dimension and has a cylindrical outer periphery of a uniform diameter, when it is to be pulled off from the die stem 1 after it is clamped by the clamp members of the handling apparatus 5, the clamp members are liable to slip on the cleaning ring 3 so that they fall to clamp the cleaning ring 3, which makes it impossible to perform an intended operation.